Halochromic Polyaniline as smart detector packaging for fresh food: a review

Abstract

Early spoilage is a challenge that is often encountered in fresh food. One prevention that can be done is by using packaging technology. There has been an increasing interest in using smart detector packaging for fresh products. Smart detector has high sensitivity and is responsive to visual changes when exposed to pH, temperature, water activity, or composition. The advantage of using a smart detector is that it can detect and give information on which products are safe to consume and which are not. Overall, the concept of a smart detector is not much different from the function of smart packaging. Smart packaging that is sensitive to pH is called halochromic properties. The mechanism of halochromic depends on the compound or the indicator used. Polyaniline (PANI) is one of the candidates for halochromic materials, which have high stability and sensitivity to pH changes. PANI also has a high sensitivity to volatile compounds such as ammonia, indicated by a change in colour from green to blue. This review will overview the use of PANI as a smart detector halochromic packaging and its potential application in the food industry. It has been found that the application of PANI has opportunities to advance the development of modern smart packaging and better food quality monitoring systems.